Movement restraining means



Aug. 23, 1938. v M. B. CAMERON MOVEMENT RESTRAINING MEANS Filed April 8, 1937 2 Sheets-Sheet 1 mv wwh w N N 0 RW 0M mA w e H E M T H o M ATTORNEY.

Aug. 23,- 1938. M. B. CAMERON MOVEMENT RESTRAINING MEANS Filed April 8, 1937 2 Sheets-Sheet 2 III " lNVEN'i'OR MORTIMER B. CAMERON BY W J A'r'roRN Patented Aug. 23, 1938 I 2,128,037

UNITED STATES PATENTTOFFICE" MOVEMENT REST'RAINING MEANS Mortimer B. Cameron, Edgewood, Pa., assignor to The Westinghouse Air Brake Company, Wilmerding, Pa., a corporation of Pennsylvania Application April 8, 1937, Serial No. 135,617 20 Claims. (Cl. 188-203) This invention relates to motion restraining juster embodyingthe invention; and Figs. 2 and means adapted to be embodied in mechanisms in 3 are cross-sectional views taken along the lines which it is desired to restrain certain operating ,2-2 and33 respectively of Fig. 1 g

elements against unintentional movement from The restraining. mechanism is shown in conm, their proper operating positions, which mechanection with 'a slack adjuster which may comnisms may include slack adjusters for brake rigprise a casing I. having at oneend. spaced arms! ging and more particularly that type of slack which are adapted to'beattached, =at theirouter adjuster in which a rotatable adjusting nut is ends, toxa brake cylinder or any other desired "employed to move a screw threaded adjusting supporting structure. Disposed between the arms n "member for either taking up or providing slack. 2 and movable longitudinally thereof is across-'10 The principal object of the present invention head 3 which is operativelyconnected at one end is to provide an improved motion restraining to a lever 4 by means of a pin 5, s'aid'lever'being means for mechanisms adapted to prevent unina part ofthe brakerigging to be adjusted.- The tentional relative movement between certain crosshead is:held against axial rotation ,in the parts of the mechanisms and adapted tobe renusual-manner by the arms 2. 15

dered ineffective to prevent intentional movement For the purpose of actuating the crosshead-a of the parts. longitudinally movable screw-threaded member 6 Slack adjusters of the above mentioned type is provided which has one end attached to the usually embody a stop or latching mechanism for crosshead by means of a rivet 1 and through the restraining the adjusting mechanism against medium ofthis connection the crosshead willpr-e- 20 i ovement in a direction to provide slack in the vent axial. rotation of the member." '1

"brake rigging, but there is nothing provided for The other end of the member Sextendsthrough restraining the mechanism against movement in an opening '8 inthe wall 9 of the casing, and the opposite or slack take up direction, the inbeyond this wall, has screw-threaded connection herent frictional resistance of the several movwith a rotatable adjusting nut 10, havingia rela- 25 able parts being relied upon to' prevent such tively short longitudinally extending. annular end movement. Under normal service shocks or viportion I2 whichis journaled in'an annular bearbrations to which the slack adjuster is subjected, 'ing l3scarried bythe casing. Theend face-of the the frictional resistance may in some instances portion I2 'slidably engages the walls of thecas- Ig0 be adequate to prevent such movement, but in ing; which wall, in the'present embodiment, of the other instances and under abnormal conditions invention constitutes a thrust bearing for thenut. -it may be wholly inadequate. It is therefore The nut for the remainder of its length is of hexpossible, under the influence of such abnormal agonal formin cross section and is telescoped by shocks or vibrations, for the mechanism to un- 1 the innenend of a rotatable hollow sleeve memintentionally function to decrease the slack in the her M, i the inner surface of the nut receiving 35 brake rigging when such decrease is undesired. p i n f th sleeve being made b n i lly i -It is therefore another object of the invention conform to the shape and dimensions of the teleto provide means for restraining the adjusting scoped portion. of the nut, to provide a positive mechanism of a slack adjuster against undesired driving Connection f m h s ee w the 1111i? 40:m0vement either to increase or decrease the slack The portion l2 of the nut, as shown in Eig,..1 40 in the brake rigging. provides a shoulder l5 against which the left A further object of the invention is to provide hand end of the sleeve I4 bears. means for restraining the adjusting mechanism The sleeve l4. extends beyond therighthand of the slack adjuster against undesired movement end of the casing I andwhere it passes through .to either decrease or increase the slack in a brake the casi it l'm i a bushing unte 45 rigging and to provide means for automatically in the casing, the inner end of the bushing concontrolling the restraining means to permit destituting athrust bearing for the outer end, face sired movement of the adjusting mechanism to of an annular collar I! which is preferably either increase or decrease the slack in thebrake formed integral with the sleeve, Which bushing ri ging. is provided with an outwardly.extendingflange 50 Other objects and advantages will appear in 18. The portion of the sleeve which-projectsbethe following more detailed description of the yond the casing is provided with an exterior nut invention. portion IQ for engagement by a tool whenit is y In the accompanying drawings Fig. 1 is a. side desired to rotate the sleeve by hand. elevational view, partly in section, of a slack ad .It is to be noted that since the end of the nut 55 a piston 22 having a stem consisting of a pair of members 23 which are spaced apart to straddle the ratchet wheel and which at their outer ends are rigidly connected together by an integral spring seat 24 cooperating with the coil spring 25 seated on the casing. The stem members- 23- are also connected together by spaced bridge pieces 26, 21 and 28.

For the purpose of driving the ratchet wheel 20 a pawl 29 is provided which is disposed b'etween-the spaced piston stem members 23 and which is pivotally mounted at one end on a pin 30 located adjacent the piston 22 and carried by and bridging the space between the members. The free end of the pawl is shaped to operatively engage the teeth of the ratchet wheel. Intermediate its ends, the pawl is provided with a lug 3| which, when the piston is in its normal position as shown in Fig. 3, is in engagement with a stop 32 incorporated in the casing and which, due to such engagement maintains the .pawl out of contact with the ratchet wheel against the opposing pressure of a spring 33 interposed between and engaging the piston and a lug '34 integral with and extending outwardly from the pivoted end of the pawl.

At one side of the piston 22 is a piston chamber 35 which is connected by way of a passage and pipe 36 to the usual slack adjuster port of a brake cylinder (not shown) in a well known manner, to establish communication through which fluid under pressure is adapted to flow to the piston chamber when the brake cylinder piston, in effecting an application of the brakes, uncovers the adjuster port.

The collar I! of the sleeve I4 is provided with outwardly extending radially arranged lugs 31, 38 and 39 which are of less width than the collar so as to provide a narrow clear space between the lugs and the flange I8 of the bushing I6. Located largely within this space and rockably mounted on the collar I1 is a mechanism which normally restrains the sleeve l4 against accidental rotation in both the slack take-up and slack'providing direction and which is automatically operative to permit the movement of the sleeve in either direction when the sleeve is intentionally subjected to force applied automatically or manually to rotate the sleeve as will hereinafter more fully appear.

This restraining mechanism in the present embodiment of the invention comprises an annular member 40 which is disposed in the space between the lugs and flange I8 of the bushing I6 and which is maintained in its proper position longitudinally of the sleeve by the lugs 31, 33 and 39 and flange I8. The member 40 is provided'with pivot pins 41 and 42 which are located outside of the sleeve l4 and preferably diametrically 0pposite to each other, and pivotally mounted on these pins are latchmembers 43 and 44, respectively, which extend at substantially right angles to the axis of the sleeve and which are rockable in opposite directions to each other either into or out of locking engagement with the stationary to the atmosphere.-

radially arranged teeth 45 preferably integral with and located interiorly of an annular portion 5| of the casing.

Each of the latch members comprises an arm 46 which is located at one side of the latch pivot and which is provided with a sloping or wedge shaped inner edge surface 48 which is, for a portion of its length, within the path of travel of the outer end of either the lug 38 or the lug 39 as the case may be. The arms 46 of the latch members are each urged into engagement with the teeth 45 by means of a spring 49 which is interposed between and engages the arm and the lug 31, the collar H at each side of the lug 41 being provided with a recess 50 to accommodate the lug engaging end of the spring.

With the latch members 43 and 44 in engagement with the teeth 45, the lower ends of the arm 47 of the members over-lie the outer ends of the lugs 38 and 39, respectively, there being a slight clearance space between the lugs and the sloping surfaces 48 of the members. This insures against the lugs interfering with the full locking movement of the latch members.

Automatic operation of the slack adjusters to take up slack .ring, the brake cylinder piston will uncover the slack adjuster port to the brake cylinder piston chamber, so that fluid under pressure will flow from this chamber through pipe and passage 36 to the piston chamber 35 of the slack adjuster cylinder. Fluid under pressure then supplied to the chamber 35 causes the piston 22 and thereby the piston stem and pawl 29 to move inwardly, the spring seat 24 carried by the stem causing the spring 25 to be compressed. As the pawl 29 is thus being moved, the spring 33 interposed between the piston and the arm 34 of the pawl, acts to cause the pawl to rotate in a clockwise direction into engagement with a tooth of the ratchetwheel 20. The adjusting motor is now in condition for operation to take up slack in the brake rigging.

Upon the release of fluid under pressure from the brake cylinder to effect a release of the brakes,-

the brake cylinder piston in its traverse toward release position first cuts off communication between the brake cylinder piston chamber and the slack adjuster port and consequently the piston chamber 35 of the slack adjuster and then connects this port and thereby the piston chamber 35 to the non-pressure chamber of the brake cylinder which is connected in the usual manner Upon the'release of fluid under pressure from the piston chamber 35, the spring 25 acts to move the piston stem, pawl 29 carried by the piston stem and piston 22 to their outer or normal position in which they are shown in Fig. 3, the pawl acting to rotate the ratchet wheel 20 and thereby the sleeve l4 and adjusting nut ID in a counterclockwise direction, as viewed in Fig. 3. The nut H] as it is thus rotated, due to its screw threaded connection with the member 5, causes the member and thereby the crosshead 3 and lever 4 to move a short distance toof the rotary movement of the sleeve by the pawl amaoav 29; the lug. 38 on the sleeve, after moving through the clearance space between the lug and the arm 41 of the-latch member 43; engages the surface 48 of the latch member and through such engagement causes the latch member to rock about the pivot pin 4| in a counterclockwise direction as view in Fig. 2, so that the end 46 of the latch member is moved out of engagement with the stationary teeth 45 carried by the casing. When the'lateh'member 43-has been moved out of engagement with the' teeth 45,v the sleeve |'4,.'asit continues to be rotated by the pawl 29, acts through the" medium of the lug 38; latch member. 43 and pivot pin 4! to rotate the member 40' and thereby the latch member 44 in the same direction as the sleeve is rotated, the latch 44 idlingover one or more of the teeth 45 according to the degree of rotation impartedtoi the sleeve and to the distance between the teeth 45.

The rotary movement of the sleeve l4 is=limited' by the automatic operation of the pawl 29 out of engagement with the ratchet wheel which operation isaccomplished in the following usual manner. Before the piston has reached its normal position, the stop 32 of the casing cooperates with' the lug 3| of the pawl to move the pawlout of engagement with the ratchet wheel so that when the piston is in its normal position the pawl will be maintained out of engagement with the ratchet wheel as shown in Fig. 3.

It should here beobserved that as the sleeve [4 isbeing rotated to effect the unlatching movement of the latch member 43, the spring 49 will be compressed by" movement of the lug 31 relative to the latch member 44 so that when the pawl 29 is moved out of engagement with the ratchet wheel 29 this spring will act to rotate the sleeve I4 in a clockwise direction, the big 38 of the sleeve, as it is thus being moved, permitting the spring 49, which is interposed between the lug 31 and the latch member'46, to move the latchmember intolocking engagement with the teeth 45. When the sleeve has been rotated in this direction a sufficient distance for the lug 38 to be free of the arm 41" of the latch member 43 the pressures of the springs" 49' acting on opposite sides of the lug- 31 will be equalized and the sleeve will come to a stop with the lugs 38 and' 39 spaced away from the arms41 of the latch members 43 and 44, respectively, as shown in- Fig. 2.

Manual operation of the slack adjuster to take up slack and to provide slack When it is desired to take up slack in the rigging manually a wrench or other suitabletool' is applied to the nut portion of the sleeveand through the medium of the tool the sleeve I4 is rotated in a counterclockwisedirection as viewed in Figs. 2 and 3, the lug 38 thereon engaging the latch member 43 and causing the latch member to be raised out of engagement with-the teeth in the same manner as" when the sleeve-is moved by the pawl 29 and ratchet Wheel 20'.v When: the desired adjustment has'been made and the operator releases the sleeve, the sleeve will move in a clockwise direction inthe same manner as has hereinbe'fore been describedin" connection with the release of the sleeve by the pawl 29- so that the lugs 38 and 39 will assume their normal positions with respect to the latch members 43 and 4 4*, respectively.

If it is desired to provide slack inthe brake rigging, as will: be the case when new brake shoes are robe substituted for worn. ones, the sleeves i4 will: be: rotatedlmanually' in a clockwise direction as viewed in Figs. 2 and 8', the lug 39 of the sleeve" engaging and actuating the latch member 44 out of engagement with the teeth 45,. the lug; 3'1 compressing the spring 49 interposed between thislug and" the latch member 43. Upon continued rotation of the sleeve I4 after the latch member 44 is. moved out of engagement with the teeth 45,. the lug 3-9, acting through the medium of the latch 44 and the pivot pin 42, causes the member 39 and latch member 43 to be rotated as a' unit in the same direction, the latch member 43 idling over the teeth 45 until such time as the desired slack has been provided, or in other words, until the operator ceases to rotate the sleeve. When the sleeve I4 is relieved of manual pressure the spring 49 interposed between the lug 31 and latch member. 43 acts to rotate the sleevein a: counterclockwise direction relative to the member 40 so that the lug. 39 will be moved away from the latch member 44 and permit the spring.- 49 interposed between the lug 31 and the latch member- 44 to move the latch member into engagement .with the teeth- 45.

General consideration Itwillbe noted that sincethe latch member 43 normally restrainsthe member 40 against rotation relative to the casing in a counterclockwise direction as viewed in Fig. 2 and the latch member 44 normally restrains the member 40 against rotationinthe opposite direction, the springs 49 actingthrough the medium of the latch member will prevent the accidental rotation of the sleeve in either direction.

While one illustrativeembodiment of the invention has been described in detail, it is not my intention to limitits scope to that embodiment or otherwise than by the terms of the appended claims.

Having-now describedm-y invention, what I claimas new and desire tosecure by Letters Patent, is: 4 c

1: In a mechanism,- in combination, astationarypa'rt; an element selectively movable in either i of two directions relativeto'said part,v and means cooperating with said part and element for preventing unintentional movement of said element in either direction and automatically movable out of such cooperative relationship upon intentional movement of said element.

2; In a mechanismnn combination, a stationary' part,-an element selectively movable in either of two directions relativeto said part, and means cooperating. with. said part and element for preventing unintentionalmovement of said element in' either direction, and means carried by said elementfor automatically moving the movement preventing means out of cooperative relationship with said stationary part upon intentional movementof the element.

3. In a mechanism, in combination, a station'- ary part, an element selectively movable in either of two directions relative to said part, and means carried. by said element and cooperating with the element and said part for preventing unintentiona'l'movementi of the element-and being automatical'l-y movable out of cooperative relationship w'ith said' part'upo'n intentional movement of the element.

4. In a mechanism, in combination, a stationazry'parnan element selectively movable in either of two directions relative to said part,and means rockably: mounted on said element and cooperating with the" elementxand said part for preventing movement of the element as long as a force applied to the element and tending to operate the element does not exceed a predetermined magnitude and automatically movable out of such cooperative relationship with said part when the operating force applied to the element exceeds said predetermined magnitude.

, 5. In a mechanism, in combination, a stationary part, an element adapted to be selectively driven in either of two directions relative to said stationary part, means cooperating with said stationary part and element for normally opposing movement of said element in either direction, the opposing force of said means being of sufiicien t magnitude to prevent accidental movement of'the element under all conditions of service, and means operative automatically for rendering the opposing means ineffective to oppose movement of the element upon applying an operating force to said element in excess of said opposing force.

6. In a mechanism, in combination, a stationary part, an element adapted to be selectively driven in either of two directions relative to said stationary part, means cooperating with said stationary part and element for normally opposing movement of said element in either direction, the opposing force of said means being of sufilcient magnitudeto prevent accidental movement of the element under all conditions of service, and means on said element for automatically rendering the opposing means inefiective to oppose movementof the element upon applying an operating force to said element in excess of said opposing force.

7. In a mechanism, in combination, a station ary part, an element rotatable relative to said part, means for opposing rotation of said element, said means comprising a rotatable member, locking means carried by said member and normally engaging said part to lock the member against rotation, resilient means coacting with said locking means and to actuate the locking means out of locking engagement withsaid part ment with said part, and means on said element adapted upon rotation of the element to engage said locking means and to actuate the locking means out of locking engagement with said part' when the operating force applied to said element is in excess of the opposing force of said resilient means acting through the locking means.

' 8. In a mechanism, in combination, a stationary part, an element rotatable relative to said part, means for opposing rotation of said element, said means comprising a rotatable member, locking means carried by said member and normally engaging said part to lock the member against rotation, resilient means coacting with said locking means and element to oppose movement'of the locking means out of locking engagement with said part, and means on said element adapted upon rotation of the element to engage said locking means and to actuate the locking means out of locking engagement with said'part when the operating force applied to said element is in excess of the opposing force of said resilient means acting through the locking means, the means for opposing rotation of said element being rotatable with the element when the locking means is out of locking engagement with said part.

9. In a mechanism, in combination, a stationary part, an element rotatable relative to said part, means for opposing rotation of said element, said means comprising a member carried ,by-said element and having a lost motion'connection therewith for at times permitting the element to rotate a limited distance relative thereto, locking means coacting with said part and element for locking said member against rotation bythe element, and means carried by the element operative upon rotation of the element a predetermined distance relative to the member for moving said locking means out of locking engagement with said part.

'10. In a mechanism, in combination, a, stationary part, an element rotatable relative. to said part, means for opposing rotation of said element, said means comprising a member carried by said element and having a lost motion connection therewith for at times permitting the element to rotate a limited distance relative thereto, locking means coacting with said part and elementfor locking said member against rotation by the element, means operative upon rotation of said element a predetermined distance relative to the member for moving said locking means out of locking engagement with said part, and means opposing the operation of the locking means.

'11. In a mechanism, in combination, a stationary part, an element rotatable relative to said part, means for opposing rotation-of said element, said means comprising a member carried by" said. element and having a lost motion connection therewith for at times permitting the element to rotate a limited distance relative thereto, locking means coacting with said part and element for locking said member against rotation by the element, means operative upon rotation of said element a predetermined distance relative to the member for moving said locking means out of locking engagement with said part, and means interposed between and engaging said locking means and element for opposing the operation of the locking means. 12. In a mechanism, in combination, a stationary part, an element rotatable relative to said part, means for opposing rotation of said element, said means comprising a member carried by said element and having a lost motion connection therewith for at times permitting the element to rotate a limited distance relative thereto, locking means coating with said part and element for locking said member against rotation by the element, means operative upon rotation of said element apredetermined distance relative to the member for moving said locking means out of locking engagement with said part, and a spring interposed betweenand engagingsaid locking means and element for opposing the operation of the locking means.

13. In a mechanism, in combination, a stationary part, an element rotatable relative to said part, means for opposing rotation of said element, said means comprising a member carried by said element and having a lost motion connection therewith for at times permitting the element to rotate a limited distance relative thereto, locking means coacting with said part and element for locking said member against rotation by the element, means operative upon rotation of said element a predetermined distance relative to the member for moving said locking means out of locking engagement with said part, and means interposed between and engaging said locking means and element for opposing the operation of the locking means and for. moving said locking means into locki g engagement with said part upon the relief of operating force on said element.

14. In a slack adjuster for brake rigging, in combination, a member movable in one direction to take up slack and movable in the opposite direction to provide slack, an element operable to move said member in either direction, and means restraining the element against accidental operation and being automatically movable out of restraining relationship with the element upon the intentional movement of the element.

15. In a slack adjuster for brake rigging, in combination, a member movable in one direction to take up slack and movable in the opposite direction to provide slack, an element operable to move said member in either direction, means restraining the element against accidental operation and being automatically movable out of restraining relationship with the element upon the intentional movement of the element, and means carried by the element for actuating the restraining means.

16. In a slack adjuster for brake rigging, in combination, a member movable in one direction to take up slack and movable in the opposite direction to provide slack, an element operable to move said member in either direction, and means restraining the element against accidental operation and being automatically movable out of restraining relationship with the element upon initiation of intentional movement of the element.

17. In a slack adjuster for brake rigging, in combination, mechanism operable to take up or provide slack: in the rigging, means normally holding said mechanism against accidental movement to either take up or provide slack and being automatically operable out of holding relationship with said mechanism upon intentional movement of the mechanism.

18. In a slack adjuster for brake rigging, in

combination, a casing, mechanism mounted in said casing operable to either take up or provide slack in the rigging, restraining means cooperating with said casing and mechanism for holding the mechanism against accidental operation to either take up or provide slack, and means included in said mechanism adapted to render said restraining means inefiective to hold said mechanism against operation upon the intentional movement of the mechanism to adjust the slack in the rigging.

19. In a slack adjuster for brake rigging, in combination, a casing, mechanism mounted in said casing operable to either take up or provide slack in the rigging, restraining means cooperating with said casing and mechanism for holding the mechanism against accidental operation to either take up or provide slack, and means included in said mechanism adapted to render said restraining means ineffective to hold said mechanism against operation upon the intentional movement of the mechanism to adjust the slack in the rigging, said restraining means being movable with said mechanism during the subsequent intentional adjusting movement of the mechanism.

20. In a slack adjuster for brake rigging, in combination, a casing, an adjusting element journalled in said casing and rotatable in one direction to take up slack in the brake rigging and rotatable in the opposite direction to provide slack in the brake rigging, means cooperating with said casing and adjusting element and carried by the element for opposing rotation of the element in either direction, and means on said element adapted only upon applying a predetermined operating force to said element for actuating the rotation opposing means out of opposing relationship with the element.

MORTIMER B. CAMERON.

CERTIFICATE 0F CORRECTION. Patent No. 2,12 ,O 7. August 2 19 8.

MORTIMER B. CAMERON.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page L first column, line 15, Claim 7, for the words "to actuate" read. element to oppose movement of; line 15, same claim, strike out "meant with said part":

and that thesaid Letters Patent shouldbe read with this correction therein that the same mayconform to the record of the case in the Patent Office.

Signed and sealed this 26th day of September; A D. 1959.

Henry Van Arsdale (Seal) I Acting Commissioner of Patents. 

